Q = m * (Lf + C * (Tf - Ti))
Where:
- Q is the amount of heat that needs to be removed (in BTU)
- m is the mass of water (in pounds)
- Lf is the latent heat of fusion for water (144 BTU/lb)
- C is the specific heat of water (1 BTU/lb-°F)
- Tf is the final temperature of the ice (17°F)
- Ti is the initial temperature of the water (32°F)
Plugging in the values, we get:
Q = 1 lb * (144 BTU/lb + 1 BTU/lb-°F * (17°F - 32°F))
Q = 1 lb * (144 BTU/lb + 1 BTU/lb-°F * (-15°F))
Q = 1 lb * (144 BTU/lb - 15 BTU/lb)
Q = 129 BTU
Therefore, 129 BTU's must be removed from one pound of water at 32°F in order to create a block of ice at 17°F.
